Bulk bag with multiple lifting mechanisms

ABSTRACT

A bulk bag and method of making the bulk bag uses stevedores and lift straps that attached to a bulk bag body so that the bulk bag has multiple lifting mechanisms.

CROSS REFERENCE TO RELATED APPLICATION

This application is entitled to the benefit of U.S. Provisional Patent Application Ser. No. 61/746,026, filed on Dec. 26, 2012, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Bulk bags are used for the transportation of bulk loose materials. Bulk bags are usually fabricated by stitching or sewing pieces of woven fabric into various shapes, including a tubular shape. A conventional bulk bag has a lifting mechanism in the form of lift straps or lifting stevedores sewn onto the body fabric so that the bulk bag can be lifted by a forklift or other lifting machinery using the lifting mechanism of the bulk bag.

Current bulk bags have various issues with respect to the lifting mechanism. As an example, for a bulk bag with lifting stevedores, a second operator is needed to guide the lifting stevedores onto the forks of a forklift or other lifting machinery because the lifting stevedores of the bulk bag do not standup by themselves. The use of a second operator increases the cost of operation, and also create a safety hazard since the second operator can be harmed by the moving machinery, e.g., the forklift As another example, for tubular bulk bags with lift straps, the lift straps attached to the body of the bulk bag in a cross-corner configuration, and thus, are not located at the corners of the bulk bag. The cross-corner configuration of the lift straps makes it hard to hook the lift straps onto a bag filling station, which typically has a receiving device onto which the lift straps are attached. As another example, current bulk bags have folded fabric at the vertical corners of the bag where the lift straps are attached. The folded fabric, together with the lift straps, protrude from the smooth surface of the bulk bag fabric, and can often catch on neighboring objects, such as another bulk bag or machinery, which can hinder movement of the bulk bag or cause damage.

SUMMARY OF THE INVENTION

A bulk bag and method of making the bulk bag uses stevedores and lift straps that attached to a bulk bag body so that the bulk bag has multiple lifting mechanisms.

A bulk bag in accordance with embodiments of the invention comprises a bulk bag body, a plurality of lift straps attached to the bulk bag body, and a plurality of stevedores attached to the bulk bag body, wherein the stevedores provide one lifting mechanism for the bulk bag and the lift straps provide another lifting mechanism for the bulk bag.

A method of making a bare bulk bag in accordance with embodiments of the invention comprises constructing a bulk bag body, attaching a plurality of lift straps to the bulk bag body, attaching a plurality of stevedores to the bulk bag body, wherein the stevedores provide one lifting mechanism for the bulk bag and the lift straps provide another lifting mechanism for the bulk bag.

Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrated by way of example of the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a tubular bulk bag in accordance with an embodiment of the invention.

FIGS. 2A, 2B and 2C illustrate a process of forming the bottom of the tubular bulk bag in accordance with an embodiment of the invention.

FIGS. 3A and 3B illustrate two variations of the process of forming the bottom of the tubular bulk bag in accordance with embodiments of the invention.

DETAILED DESCRIPTION

It will be readily understood that the components of the embodiments as generally described herein and illustrated in the appended figures could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by this detailed description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussions of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.

Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention.

Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the present invention. Thus, the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

With reference to FIG. 1, a tubular bulk bag 100 in accordance with an embodiment of the invention is described. As described in detail below, the tubular bulk bag 100 uses stevedores that are comprised of relatively stiff material so that the stevedores can stand up by themselves. Thus, there is no need for a second operator to guide the stevedores onto forklift forks or other lifting machinery. The tubular bulk bag 100 also uses corner lift straps that are soft and located close to the corners of the bulk bag so that the corner lift straps can be easily hooked onto a filling station. The tubular bulk bag 100 also uses a tubular fabric body that does not catch on other bulk bags or machines. The tubular bulk bag 100 uses less material and takes less time to make.

As illustrated in FIG. 1, the bulk bag 100 includes a bulk bag body 102 that is formed of a top portion 104, a bottom portion 106 and a side portion 108. The bulk bag body 102 can be comprised of a tubular fabric without seams, or can be formed by connecting panels of fabric together in a way it does not produce significant protrusions from the body surface. In an embodiment, the bulk bag body 102 is made of a polypropylene woven fabric.

The tubular bag 100 has one lifting mechanism that comprises stevedores 110 and another lifting mechanism that comprises corner lift straps 112 and optional lift loops 114. The stevedores 110 are attached to the bulk bag body 102 using appropriate attaching means, such as by sewing or gluing. The corner lift straps 112 are also attached to the bulk body 112 using appropriate attaching means, such as by sewing or gluing. In the illustrated embodiment, the stevedores 110 and the corner lift straps 112 are placed at or near the corners of the bulk body. As used herein, being close to a corner or a component of the bulk bag 100 means being positioned six (6) inches or closer to the corner or component. The stevedores 110 and the corner lift straps 112 can be on top of each other, side by side, or in any configuration close to each other. The lift loops 114 are chain linked with the corner lift straps 112. The lift loops 114 are optional, and thus, in some embodiments, the tubular bulk bag does not have any lift loops.

The tubular bag 100 further includes a perimeter band 116 that covers the stevedores 110, the corner lift straps 112 and a portion of the bulk bag body 102, e.g., a portion of the side portion 108, using appropriate attaching means, such as by sewing or gluing. Different orders of attachment between the perimeter band 116, the stevedores 110, the corner lift straps 112 and the bulk bag body 102 are possible. In a first embodiment, the order of attachment from the inside to the outside of the bulk bag 100 can be (1) the bulk bag body 102, (2) the stevedores 110, (3) the corner lift straps 112 and (4) the perimeter band. In a second embodiment, the order of attachment from the inside to the outside of the bulk bag 100 can be (1) the stevedores 110, (2) the bulk bag body 102 (3) the corner lift straps 112 and (4) the perimeter band. In a third embodiment, the order of attachment from the inside to the outside of the bulk bag 100 can be (1) the stevedores 110, (2) the corner lift straps 112, (3) the bulk bag body 102 and (4) the perimeter band. In a fourth embodiment, the order of attachment from the inside to the outside of the bulk bag 100 can be (1) the corner lift straps 112, (2) the stevedores 110, (3) the bulk bag body 102 and (4) the perimeter band. Any other stacking orders among the perimeter band 116, the stevedores 110, the corner lift straps 112 and the bulk bag body 102 are also possible.

In an embodiment, the stevedores 110 can be extended toward the bottom portion 106 of the bulk bag body 102 but not reach the bottom portion, as shown in FIG. 1. In other embodiments, the stevedores 110 can be further extended to be attached onto the bottom portion 106 of the bulk bag body 102 from either the inside or the outside of the bulk bag body.

Similarly, in an embodiment, the corner lift straps 112 can be extended toward the bottom portion 106 of the bulk bag body 102 but not reach the bottom portion, as shown in FIG. 1. In other embodiments, the corner lift straps 112 can be further extended to be attached onto the bottom portion 106 of the bulk bag body 102 from either the inside or the outside of the bulk bag body. The two ends of each corner lift strap 112, which are attached onto one of the stevedores 110, the perimeter band 116 and the bulk bag body 102, can be side by side, one on top of the other, separated by one of the stevedores, the perimeter band and the bulk bag body, or in any other configuration as long as the two corner lift strap ends are close to the corner of the bulk bag body. The two ends of each corner lift strap 112 can wholly or partially cover one of the stevedores 110, or can be side by side with and close to that stevedore. The two ends of each corner lift strap 112 attached to the bulk bag body 102 can be vertical or at an angle of as much as 30 degrees from the vertical orientation.

The ends of the stevedores 110 attached to the bulk bag body 102 can be in a single strip for or two or more strips side by side, or separated by one of the corner lift straps 112, but still close to the corners of the bulk bag body. The top portion of each stevedore 110 can be the same as the bottom portion of the stevedore, or the top portion of the stevedore can be folded, once or more, to make it narrower for ease of use and higher strength.

The stevedores 110 of the tubular bulk bag 100 can be made of relatively stiff material so that the stevedores can stand up above the bulk bag body 102, and thus, do not fall down under their weight when not in use. Thus, a forklift operator can drive the forklift forks into the space under the top portion of the stevedores 110 without the need of a second person to hold the stevedores up.

The corner lift straps 112 of the tubular bulk bag 100 can be made of relatively soft material so that the lift straps fall down under their weight when not in use. Thus, it is easier to hook the corner lift straps 112 onto a filling machine and the corner lift straps can drop down naturally by themselves once released from the filling machine. Therefore, when the corner lift straps 112 are not in use, the corner lift straps do not cause any hindrance to other objects in operation. The corner locations of the corner lift straps 112 make it easier to place the corner lift straps onto a filling station. The perimeter band 116 strengthens the attachment of the stevedores 110 and the corner lift straps 112, especially during situations when the corner lift straps or the stevedores are pulled sideways away from the bulk bag body 102.

In an embodiment, the tubular bulk bag 100 can be fabricated by first forming the side portion 108 of the bulk bag body 102 by cutting a tubular fabric into a certain length, or by connecting panels of flat fabric to form a tubular body. The top portion 104 and the bottom portion 106 of the bulk bag body 102 are prepared from a single piece of fabric, or can be prepared by connecting multiple pieces of fabric together. The stevedores 110, the corner lift straps 112, the perimeter band 116 and the lift loops 114 are all prepared by cutting from a longer piece of material.

The side portion 108 of the bulk bag body 102, the stevedores 110, the corner lift straps 112 and the perimeter band 116 are attached together by sewing or other attaching means. The order of attachment between the side portion 108 of the bulk bag body 102, the stevedores 110, the corner lift straps 112 and the perimeter band 116 can vary, as explained above. The lift loops 114 can also be attached during this step or the lift loops 114 can be formed before this step by running an open piece of strap material through each of the corner lift straps 112, and connecting and overlapping the ends of the material to form a closed ring for each corner lift strap. The top portion 104 and the bottom portion 106 of the bulk bag body 102 are then attached to the side portion 108 of the bulk bag body.

These steps of fabricating the tubular bulk bag 100 do not have to follow the above-described order. Some of the fabricating steps can be done concurrently, and some of the fabricating steps can be done in other sequences.

The side portion 108 of the bulk bag body 102 is a necessary component of the tubular bulk bag 100. The bottom portion 106 of the bulk bag body 102 is also necessary component for the function of the tubular bulk bag 100, although the bottom portion can be of different shape and configuration. The stevedores 110 and the corner lift straps 112 are also necessary components for the functions of the bulk bag 100. The perimeter band 116 is an optional component. The perimeter band 116 is used to enhance the strength of the bulk bag 100. The lift loops 114 are optional components. The top portion 104 of the bulk bag body 102 is an optional component. The tubular bulk bag 100 can be without any type of top. However, if included, the top portion 104 of the bulk bag body 102 can be of different shapes.

The tubular bulk bag 100 can be used in the following manner in accordance with an embodiment of the invention. The corner lift straps 112 are used on a filling station by hooking the corner lift straps onto a receiving device of the filling station. The lift hoops 114, which are connected to the corner lift straps 112, can be used to lift up the tubular bulk bag 100 by placing the lift hoops onto forklift forks or other machinery. In order to use the stevedores 110, the forklift forks are moved into the space under the top portions of the stevedores. Since the stevedores 110 of the tubular bulk bag 100 stand up on their own, there is no need to have a second person holding them up while the forklift forks are maneuvered into the space under the top portions of the stevedores. This reduces the operation cost and eliminates a safety hazard of the second person being potentially harmed by the moving forklift forks.

In an embodiment, the tubular bulk bag 100 uses the tubular body fabric itself, i.e., the side portion 108, to form the bag bottom instead of using a separate piece of fabric to form the bottom portion 106 of the bulk bag. The connection between the bottom portion 106 to the side portion 108 may be a weak area on the bulk bag 100. The use of the tubular body fabric itself to form the bag bottom may increase the strength of the tubular bulk bag 100.

The process of forming the bottom of the tubular bulk bag 100 using the tubular fabric, i.e., the side portion 108, is described with reference to FIGS. 2A, 2B, 2C, 3A and 3B. As illustrated in FIGS. 2A and 2B, the four bottom corners of the tubular fabric, i.e., the side portion 108, are sewn along sewing lines 220, which are at an angle θ. The angle θ of the sewing lines 220 can be 45 degrees from the vertical direction, which results in a flat bag bottom, or less than 45 degrees, which results in a cone-like bottom. The bottom corners are then folded flat and attached onto the tubular fabric using an appropriate attaching means, such as by sewing or gluing, as illustrated in FIG. 2C.

There are two variations of the process of forming the bottom of the tubular bulk bag 100. The first variation is illustrated in FIG. 3A, which would replace FIG. 2C in the original process illustrated in FIGS. 2A, 2B and 2C. In the first variation, part of the bottom corner tips of the tubular fabric is cut off or otherwise removed, but there is still enough fabric to fold the remaining corners flat and attach them to the tubular fabric using an appropriate attaching means, such as by sewing or gluing. The second variation is illustrated in FIG. 3B, which would replace FIG. 2C in the original process illustrated in FIGS. 2A, 2B and 2C. In the second variation, the bottom corners of the tubular fabric are folded and attached using an appropriate attaching means, such as by sewing or gluing, without the initial sewing along the sewing lines 220.

Although specific embodiments of the invention have been described and illustrated, the invention is not to be limited to the specific forms or arrangements of parts so described and illustrated. In particular, the bulk bag 100 may be configured The scope of the invention is to be defined by the claims appended hereto and their equivalents. 

What is claimed is:
 1. A bulk bag comprising: a bulk bag body; a plurality of lift straps attached to the bulk bag body; and a plurality of stevedores attached to the bulk bag body, wherein the stevedores provide one lifting mechanism for the bulk bag and the lift straps provide another lifting mechanism for the bulk bag.
 2. The bulk bag of claim 1 wherein the lift straps and the stevedores are attached to the bulk bag body near top corners of the bulk bag body.
 3. The bulk bag of claim 1 wherein the bulk bag body is made of a polypropylene woven fabric.
 4. The bulk bag of claim 1 wherein the lift straps are made of relatively soft material so that the lift straps fall down under their weight when not in use.
 5. The bulk bag of claim 1 wherein the stevedores are made of relatively stiff material so that the stevedores stand up and do not fall down under their weight when not in use.
 6. The bulk bag of claim 1 further comprising lift loops connected to the lift straps.
 7. The bulk bag of claim 1 further comprising a perimeter band attached to the bulk bag body over the lift straps and the stevedores.
 8. The bulk bag of claim 1 wherein the order of attachment between the bulk bag body, the lift straps and the stevedores from the inside of the bulk bag to the outside of the bulk bag is any possible order.
 9. The bulk bag of claim 1 wherein the bulk bag body includes a bottom portion and a side portion, the side portion being a single tubular piece of fabric.
 10. The bulk bag of claim 9 wherein the bottom portion of the bulk bag body is part of the single tubular piece of fabric.
 11. The bulk bag of claim 19 wherein the bottom portion of the bulk bag body is another piece of fabric attached to the single tubular piece of fabric.
 12. A method of making a bulk bag, the method comprising: constructing a bulk bag body; attaching a plurality of lift straps to the bulk bag body; and attaching a plurality of stevedores to the bulk bag body, wherein the stevedores provide one lifting mechanism for the bulk bag and the lift straps provide another lifting mechanism for the bulk bag.
 13. The method of claim 12 wherein the lift straps and the stevedores are attached to the bulk bag body near top corners of the bulk bag body.
 14. The method of claim 12 wherein the lift straps are made of relatively soft material so that the lift straps fall down under their weight when not in use.
 15. The method of claim 12 wherein the stevedores are made of relatively stiff material so that the stevedores stand up and do not fall down under their weight when not in use.
 16. The method of claim 12 further comprising connecting lift loops to the lift straps.
 17. The method of claim 12 further comprising attaching a perimeter band attached to the bulk bag body over the lift straps and the stevedores.
 18. The method of claim 12 wherein constructing the bulk bag body includes attaching a piece of fabric to a tubular piece of fabric to form a bottom portion of the bulk bag body.
 19. The method of claim 12 wherein constructing the bulk bag body includes folding bottom corners of a tubular piece of fabric and attaching folded portions to the tubular piece of fabric to form a bottom portion of the bulk bag body. 